There is often an apparent misconception that there is more movement in these days of railways and steamers and motors than existed ten centuries before Christ. The difference lies not in the comparative amount of movement but in the method of it. In one sense only is there more movement--there are more people to travel; but in a broader sense there is much less movement. Whole nations are no longer shifted at the will of the conqueror across a continent, trade seekers no longer devote their lives to the personal conduct of caravans; armies swelled to prodigious size by a tagrag following no longer (except in China) move slowly over the face of the land, devouring, like a swarm of locusts, all that comes in their way. Colonial emigration perhaps alone works on a larger scale now than in those early times; but taking it "bye and large," the circulation of the human race, unrestricted by political boundaries, was certainly more constant in the unsettled days of nomadic existence than in these later days of overgrown cities and electric traffic. If little or nothing is recorded of many of the most important migrations which have changed the ethnographic conditions of Asia, whilst at the same time we have volumes of ancient philosophy and mythology, it is because such changes were regarded as normal, and the current of contemporary history as an ephemeral phenomenon not worth the labour of close inquiry or a manuscript record. Such a gazetteer as that presented to us by Herodotus would not have been possible had there not been free and frequent access to the countries and the people with whom it deals. It is impossible to conceive that so much accuracy of detail could have been acquired without the assistance of personal inquiry on the spot. If this is so, then the Persians at any rate knew their way well about Asia as far east as Tibet and India, and the Greeks undoubtedly derived their knowledge from Persia. When Alexander of Macedon first planned his expedition to Central Asia he had probably more certain knowledge of the way thither than Lord Napier of Magdala possessed when he set out to find the capital of Theodore's kingdom in Abyssinia, and it is most interesting to note the information which was possessed by the Greek authorities a century and a half before Alexander's time.